1. Field of Invention
This invention relates to enclosures that insulate people from sleep-disturbing noises.
Sleep Deprivation in an Increasingly Noisy World
Many people live and sleep in places that are increasingly noisy. Our modern world is permeated by: intrusive sound systems with powerful bass speakers that penetrate apartment walls, video games with loud explosions and sound effects, vehicles with thumping bass speakers, jet and train traffic at all hours of the day and night, sirens and heavy equipment, dogs that bark incessantly, and so forth. The list of noise pollution sources grows each year. High noise levels are bad enough during daylight hours, but can be especially devastating at night when one is trying to sleep. Lack of sleep due to environmental noise can wreak havoc on one's health, productivity, and overall quality of life. Sleep-disturbing noise can even come from members of one's own household. For example, loud snoring can have devastating effects on one's closest personal relationships.
Some people can afford to live in places that are far removed from the flight paths of major airports, but other people can not. Some people can afford to live far away from establishments that play loud music until the early morning hours, but other people can not. Some people can afford to have living arrangements with multiple bedrooms so that they do not have to choose between a close relationship and getting enough sleep to face the next day, but other people can not. For many people, sleep deprivation is a vicious cycle. Sleep deprivation hinders them from earning more income, the limited income limits their living options, and the limited living options result in more sleep deprivation. What can be done to break this cycle to help people to get a decent night's sleep in today's increasingly noisy world?
For all of these reasons, there is a significant and growing need for safe methods to reduce exposure to intrusive sounds so that people can get a decent night's sleep. There are methods in the related art that reduce a sleeper's exposure to environmental sounds. However, as we will discuss, these methods in the related art have significant limitations. A very-real unmet need remains. The invention disclosed herein is designed to meet this need in an innovative, safe, and useful manner. There does not appear to be anything in the prior art that anticipates this invention. This invention can help many people to avoid the devastation of chronic sleep deprivation on their health, relationships, productivity and overall quality of life.
There are two general approaches in the related art that are directed toward reducing the detrimental effects of sleep-disturbing noise. The first approach involves generating sounds that cancel the sleep-disturbing noise (“noise cancellation) or mask the sleep-disturbing noise (“noise masking”). The second approach involves the use of sound-insulating structures or enclosures that block the sleep-disturbing noise from reaching the sleeper. We now discuss both of these approaches and their limitations. Following that, we describe the current invention and discuss how it addresses these limitations in an innovative and useful manner.
2. Related Art
Noise Cancellation and Noise Masking
“Noise cancellation” involves monitoring the environment for sleep-disturbing noise and then custom-generating noise-canceling sounds that have a wave structure that is symmetrically-opposite to the sleep-disturbing noise. Ideally, when the sleep-disturbing sound waves and the custom-generated sound waves overlap, their acoustic energies cancel each other out because their wave patterns are symmetrically-opposite to each other. Although appealing in theory, such noise cancellation can be difficult to do well in practice. For example, generation of sounds in order to cancel the environmental noise is not instantaneous. The environmental noise must be detected and analyzed. This creates a lag between the two sounds. If the environmental noise is relatively continuous, then this lag need not be a problem. However, if the environmental noise is intermittent or highly-variable, then the lag is a problem. Then the lagged sound waves do not cancel each other out.
One solution to address the lag problem is to have the noise monitor be closer to the noise source than the speaker that emits the custom-generated sounds and the sleeper's ear. However, this solution to the lag problem only works if the environmental noise consistently comes from the same direction. This solution breaks down when environmental noise comes from different directions. Noise-cancellation headphones can come close to canceling noise from any direction. However, many people do not like to wear headphones when they sleep and even headphones do not completely eliminate the lag problem. For these reasons, active noise cancellation is not an ideal solution for reducing sleepers' exposure to environmental noise.
“Noise masking” involves playing sounds that cover up (but do not cancel) intrusive environmental noise. Many noise masking devices create sounds with a broad-spectrum of frequencies, such as “white noise” or “pink noise,” that cover up noise at random. Other noise masking devices offer a menu of sounds from which the sleeper can select to cover up particular environmental sounds. Both types of noise masking have limitations. Broad-spectrum random sounds (such as “white noise” or “pink noise”) may not be powerful or targeted enough to mask certain sounds, such as those with powerful bass frequencies. Sounds selected from a menu of sounds may have gaps between sounds or repetition in pre-recording sound loops that let the environmental sounds come through periodically or may themselves become annoying.
An overall limitation of using one sound to cover up another sound is analogous to using one smell to cover up another smell. Sometimes the sensory organ is just not fooled. For example, trying to cover up the smell of a wet dog with a flower scent might not fool one's nose. Trying to cover up a bass beat from the party next door with the sound of a bubbling waterfall might not fool one's ears. The combined effect can sometimes be doubly annoying, not relaxing.
Some of the many examples in the related art that appear to use noise cancellation or noise masking include U.S. Pat. Nos. 5,844,996 (Enzmann et al., 1998), and 6,014,345 (Schmadeka, 2000).
3. Related Art
Sound-Insulating Sleeping Structures
Sound-insulating structures and enclosures in which one or more people sleep can block some or all of the sleep-disturbing noise from the environment that would otherwise reach them. However, such structures have a central limitation that has not yet been solved in the prior art. This central limitation concerns the degree to which the structure fully encloses the sleeper. A structure that fully encloses the sleeper with no gaps in its walls (but does have active ventilation to provide fresh air) can thoroughly insulate a sleeper from sleep-disturbing environmental noise. However, many people do not like the “closed in” feeling of sleeping in a fully-enclosed structure if this can be avoided. They prefer a more open structure with one or more good-sized openings. Much of the related art on sound-insulating sleeping enclosures involves attempts to find the “optimal balance” between: the sound-blocking benefits of a fully-enclosed sleeping structure on the one hand vs. the aesthetic/ventilation benefits of a relatively-open sleeping structure on the other hand.
This problem is compounded because the “optimal balance” between a structure that is more open vs. a structure that is more closed often depends on circumstances and these circumstances change over time. The “optimal balance” can even change during the course of one night. For example, suppose that there is a wild party in the apartment next door and that thumping bass comes through your walls until 3 am. Under these circumstances, you may be willing to tolerate the aesthetic unpleasantness of sleeping in a relatively closed structure (as long as there is active ventilation) in order to get to sleep. However, when the circumstances change and the party stops at 3 am, then you may prefer a relatively open sleeping structure (more like a conventional bed) for aesthetic reasons and for natural ventilation. Conversely, if all is calm when you go to bed at 11 pm, then you may enjoy going to sleep in an open sleeping structure. However, when circumstances change and dog next door begins barking at nothing between 3 am and 4 am, then an enclosed structure may be preferred.
Frazzled and frustrated sleepers have struggled with changing circumstances such as these for decades. The classic image that comes to mind is that of a person who tosses and turns, placing pillows and blankets over their ears, during the course of the night. Unfortunately, pillows and blankets do not provide good sound insulation. Alternatively, if a sleeper can afford both a traditional open bed and one of the relatively-closed sound-insulating structures (with active ventilation) in the related art, then they might move back and forth from one to the other during the night with changes in environmental noise levels. However, this is resource intensive and such movement itself can disrupt one's sleep. None of the structures in the related art offer a sound-insulating solution that automatically changes from an open configuration to a closed configuration in response to changes in sound levels. This present invention provides such a solution.
Examples of sound-insulating structures for sleeping that are relatively open (having openings, screens, or nets) include the following: U.S. Pat. Nos. 2,375,941 (Nostrand, 1945), 3,323,147 (Dean, 1967), 4,377,195 (Weil, 1983), 5,560,058 (Smith, 1996), 6,446,751 (Ahuja et al., 2002), 4,017,917 (Brown, 1977), 4,305,168 (Holter et al., 1981), 4,594,817 (McLaren et al., 1986), 5,669,088 (McNamee, 1997), 6,308,466 (Moriarty, 2001), 4,641,387 (Bondy et al., 1987), 5,384,925 (Vail, 1995), 6,216,291 (Eads et al., 2001), 6,263,529 (Chadwick et al., 2001), 6,487,735 (Jacques et al., 2002), 6,694,547 (Vail, 2004), 6,772,458 (Ellen et al., 2004), 7,047,991 (Kline, 2006), 7,380,296 (Ellen et al., 2008), and 7,434,280 (Cyr, 2008), and U.S. Patent Application 20070294827 (Carr et al., 2007). Examples of sound-insulating structures for sleeping that are relatively fully-enclosed include the following: U.S. Pat. Nos. 4,109,331 (Champeau, 1978), 4,129,123 (Smidak, 1978), 4,937,903 (Joly et al., 1990), 6,461,290 (Reichman et al., 2002), 6,508,850 (Kotliar, 2003), and 6,827,760 (Kutt et al., 2004).